Method and system for compensating the vibrations of rotating components

ABSTRACT

Flexural vibrations are reduced in rotating components, such as rotating cylinders of a rotary printing press. One or more actuators are placed in a groove or recess in the cylinder. These actuators act in the axial direction of the rotating component. The amount of force exerted by said actuator will vary with the rotational position of the cylinder.

[0001] The invention relates to a method, as well as to an arrangement,in accordance with the preamble of claims 1, 28 and 31.

[0002] A method and a device for reducing bending vibrations in rotatingsystems is known from WO 97/03832.

[0003] It is the object of the invention to reduce bending vibrations inrotating components.

[0004] In accordance with the invention, this object is attained bymeans of the characteristics of claims 1, 28 and 31.

[0005] The advantages which can be achieved by means of the inventionreside in particular in that bending vibrations are reduced. Thereduction of the so-called “channel beats” of cylinders of rotaryprinting presses is of particular advantage.

[0006] An exemplary embodiment of the invention is represented in thedrawings and will be described in greater detail in what follows.

[0007] Shown are in:

[0008]FIG. 1, a front view of a cylinder of a rotary printing press inthe state of rest,

[0009]FIG. 2, a front view analogously to FIG. 1 in the operationalstate,

[0010]FIG. 3, a cross section III-III through the cylinder in FIG. 1 inan enlarged view,

[0011]FIG. 4, a cross section through a cylinder of a rotary printingpress in accordance with a further exemplary embodiment.

[0012] A rotating component, for example a cylinder, such as a formecylinder, transfer cylinder, counter-pressure cylinder, damping or guiderollers—called cylinder 01 in what follows—has journals, notrepresented, on both sides. An annular groove 06 is provided on thecircumference 04 of the cylinder 01 and approximately in the center ofthe barrel length 1, which receives a multitude of actuators, forexample actuators 20 to 31. The actuators 20 to 31 are arranged insidethe circumferential line of the cylinder 01.

[0013] It is also possible to arrange a multitude, for example three orfive, annular grooves 06, which are spaced apart in the axial directionand have actuators 20 to 31, on the cylinder 01. In the axial directionmeans in the direction of the axis of rotation 07 of the cylinder 01.

[0014] Each annular groove 06 can be filled, for example with a curableplastic material, in the direction of the surface area of the cylinder01.

[0015] The actuators 20 to 31 can consist, for example, of piezoelements or double-layer elements. Moreover, each activator can consistof a cylinder-piston unit, which can be pneumatically or hydraulicallyactuated.

[0016] It is furthermore advantageous to employ an actuator which haslayered piezo threads with copper foil anodes. The length of thisactuator is increased when a voltage is applied.

[0017] Sensors, for example piezo-ceramic printing pressure sensors, canbe arranged on the surface area of the cylinder 01. These can beunderneath the rubber blanket of the printing forme of the cylinder 01.The actuators 20 to 31, as well as the sensors, can be connected with acontrol device. The control device can be arranged inside or alsooutside of the cylinder 01.

[0018] It is also possible to employ each actuator 20 to 31simultaneously as a sensor.

[0019] The transfer of energy and/or transfer of information between thecontrol device and the sensors, as well as between the control deviceand the actuators, is preferably made in a contactless manner.

[0020] The actuators 20 to 31 can be connected with each other by meansof a control line 08.

[0021] The cylinder 01 has a channel 09, which is located in anaxis-parallel direction, as well as in the vicinity of the circumference04. This channel 09 contains known technical means for keeping in placeand/or bracing the ends of printing formes or rubber blankets of thecylinder 01 or of the roller. Also, a compensating bore 11 for receivingmeans for removing imbalances can be provided in the cylinder 01.

[0022] The arrangement operates as follows: at a defined location of thecircumference 04 and at one and/or several defined times, the sensors oralso actuators determine the actual values of the bending of thecylinder 01 in the operating state. These values are supplied to thecontrol device, which in turn acts with a defined value on therespective actuators 20 to 31. These actuators 20 to 31 change theirsize in the axial, or nearly axial, direction of the cylinder. Nearlyaxial direction means having at least one axial component. In this waythe cylinder 01 is stretched, or extended or shortened, at one, orseveral defined locations at the respective time, which affects thebending of the cylinder 01.

[0023] The force component, or size of the actuator 20 to 31, in theaxial direction is changed as a function of the direction of the angleof rotation of the cylinder 01.

[0024] In accordance with another embodiment variation (FIG. 4), arotating component, for example a cylinder 12 or a roller of a rotaryprinting press can have a channel 13 extending in an axis-paralleldirection which, for example, has a blind bore 16 for receiving anactuator 17 on its bottom area 14. This actuator 17 can be arranged atthe center of the barrel length of the cylinder 12 and can be embodiedin the form of so-called “adaptronics”. It is of course also possible toarrange several actuators, which are spaced apart from each other in theaxial direction of the cylinder 12, under the cylinder surface area.

[0025] Finally, it is also possible to provide the actuators 20 to 31with a bias voltage, regardless of whether they are electrically orpneumatically operable actuators. In this case each actuator 20 to 31already has an average longitudinal extension a (FIG. 1) in the positionof rest of the cylinder 01.

[0026] In the operating state of the cylinder 01 in accordance with FIG.2, an amount d of bending of the cylinder 01 is achieved in that theactuator 20 is charged with a greater voltage than its bias voltage upto then had amounted to—i.e. it increases in size—and the actuator 28 ischarged with a lesser voltage than the previous bias voltage, so that itis reduced in size. Because of this the actuator 20 has a greater lengthb, and the actuator 26 a lesser length c, wherein the lengths are b>a>c.

[0027] The actuators 21 to 25 and 31 to 27 located on the circumference04 between the actuator 20 and the actuator 26 can each be charged withdifferent voltages in accordance with their angular position, so thatthis causes different length changes at the cylinder circumference 04 ata defined time.

[0028] In the course of this the actuators 20 to 22, or 30, 31 locatedon a first short half of the circumference 04, increase the previousamounts a of their longitudinal extension to the new amounts b, oramounts between a and b.

[0029] The actuators 24 to 28, located on a second short half of thecircumference 04, reduce the previous amounts a of their longitudinalextensions to the new amounts c, or amounts between a and c.

[0030] Since the cylinder 01 rotates, the lengths of the actuators 20 to31 change in accordance with the angle of rotation.

[0031] Accordingly, vibrations occurring in cylinders 01 or 12 arecompensated by means of at least one actuator 17 or 20 in that a partialchange of the length of the cylinder 01 or 12 parallel with its axis ofrotation 07 is generated. Bending of the cylinder is affected by this.

[0032] Thus, the size of an amplitude of bending vibrations is reducedand/or a frequency of the bending vibrations is changed by means of theactuator 17 or 20. The bending vibrations can also affect other types ofvibrations, in particular torsional vibrations.

[0033] List of Reference Numerals 01 Rotating component, cylinder 02 —03 — 04 Circumference (01), circumferential line 05 — 06 Annular groove07 Axis of rotation 08 Control line 09 Channel 10 — 11 Compensation bore(01) 12 Rotating component, cylinder 13 Channel (12) 14 Bottom surface(13) 15 — 16 Blind bore (14) 17 Actuator (12) 18 — 19 — 20 Actuator (01)21 Actuator (01) 22 Actuator (01) 23 Actuator (01) 24 Actuator (01) 25Actuator (01) 26 Actuator (01) 27 Actuator (01) 28 Actuator (01) 29Actuator (01) 30 Actuator (01) 31 Actuator (01) 1 Barrel length (01) aLength, average, in state of rest b Length, greater c Length, lesser dAmount, bias voltage (01)

1. An arrangement for reducing bending vibrations in rotating components(01) by means of the use of at least one actuator (17, 20 to 31),characterized in that the actuator (17, 20 to 31) arranged in therotating component (01) has a force component acting in the axialdirection of the rotating component (01), that the force component ofthe actuator (17, 20 to 31) is adjustable in the axial direction as afunction of the angle of rotation position of the rotating component(01, 12).
 2. An arrangement for reducing bending vibrations in rotatingcomponents (01) by means of the use of at least one actuator (17, 20 to31), characterized in that the actuator (17, 20 to 31) arranged in therotating component (01) has a force component acting in the axialdirection of the rotating-component (01), that the actuator (17, 20 to31) is arranged in the vicinity of the circumference (04) of therotating component (01).
 3. An arrangement for reducing bendingvibrations in rotating components (01) by means of the use of at leastone actuator (17, 20 to 31), characterized in that the actuator (17, 20to 31) arranged in the rotating component (01) has a force componentacting in the axial direction of the rotating component (01), that theactuator (17, 20 to 31) is arranged so it affects the bending of therotating component (01).
 4. An arrangement for reducing bendingvibrations in rotating components (01) by means of the use of at leastone actuator (17, 20 to 31), characterized in that the actuator (17,circumferential direction of the rotating component (01).
 5. Anarrangement for reducing bending vibrations in rotating components (01)by means of the use of at least one actuator (17, 20 to 31),characterized in that the actuator (17, 20 to 31) arranged in therotating component (01) has a force component acting in the axialdirection of the rotating component (01), that the actuators (20 to 31)are arranged in a ring shape on the circumference (04) of the rotatingcomponent (01).
 6. The arrangement in accordance with one of claims 1 to5, characterized in that several actuators (20 to 31) are arranged inthe circumferential direction of the rotating component (01).
 7. Thearrangement in accordance with one of claims 1 to 5, characterized inthat several actuators (20 to 31) are arranged in the axial direction ofthe rotating component (01).
 8. The arrangement in accordance with claim6, characterized in that the actuators (20 to 31) are arranged in a ringshape on the circumference (04) of the rotating component (01).
 9. Thearrangement in accordance with claim 6 or 7, characterized in that theactuators (20 to 31) are arranged inside the circumferential line (04)of the rotating component (01).
 12. The arrangement in accordance withclaim 10, characterized in that the annular grooves (06) which containactuators (17, 20 to 31) can be filled or closed in the direction towardthe surface area of the rotating component (01).
 13. The arrangement inaccordance with claim 1, 2, 3, 4, 5, 6 or 7, characterized in that theactuators (17, 20 to 31) can be connected with a control device.
 14. Thearrangement in accordance with one of claims 1 to 5, characterized inthat the actuator (17, 20 to 31) is embodied as a piezo element.
 15. Thearrangement in accordance with one of claims 1 to 5, characterized inthat the actuator (17, 20 to 31) consists of a double-layer element. 16.The arrangement in accordance with one of claims 1 to 5, characterizedin that sensors are arranged on the surface area of the rotatingcomponent (01).
 17. The arrangement in accordance with claim 16,characterized in that the sensors can be connected with the respectiveactuators via the control device.
 18. The arrangement in accordance withclaim 13, characterized in that the control device is arranged outsidethe rotating component (01).
 21. The arrangement in accordance with oneof claims 1 to 5, characterized in that the actuator (17, 20 to 31) isembodied as a sensor.
 22. The arrangement in accordance with one ofclaims 1 to 5, characterized in that the rotating component (01) isembodied as a cylinder of a printing press.
 23. The arrangement inaccordance with claim 22, characterized in that the cylinder (01) isembodied as a forme cylinder.
 24. The arrangement in accordance withclaim 22, characterized in that the cylinder (01) is embodied as atransfer cylinder.
 25. The arrangement in accordance with claim 20,characterized in that the cylinder (01) is embodied as acounter-pressure cylinder.
 26. The arrangement in accordance with one ofclaims 1 to 5, characterized in that the rotating component (01) isembodied as a roller, in particular an ink, dampening or guide roller,of a rotary printing press.
 27. The arrangement in accordance with claim6, characterized in that actuators (20 to 31) which are arranged, spacedapart from each other at the circumference (04), cause different sizedlength changes (b, c, between b and c) of the
 29. The arrangement inaccordance with claim 6, characterized in that at least the actuators(24 to 28) located on a second short half of the circumference (04)decrease their longitudinal extension.
 30. An arrangement for reducingbending vibrations in rotating components (01) characterized in that atleast one actuator (17, 20 to 31) with at least one force componentacting in the axial direction of the rotating component (01, 12) forchanging the length and the bending of the component (01, 12) isarranged in the rotating component (01, 12).
 31. The arrangement inaccordance with claim 27, characterized in that the actuator (17, 20 to31) is arranged inside the component (01, 12) and is located underneatha channel (13) extending in an axis-parallel direction, as well as nearthe circumference of the component (01, 12).
 32. The arrangement inaccordance with claims 1 or 30, characterized in that the forcecomponent of the actuator (17, 20 to 31) is changeable in the axialdirection as a function of the angle of rotation position of therotating component (01, 12).
 33. A method for compensating vibrations inrotating component (01, 12) of rotary printing presses by means of atleast one actuator (17, 20 to 31), characterized in that at least apartial change in the length (a, b, c) of the rotating component (01,12) parallel with the axis of rotation (07) of the rotating component(01, 12) is generated by means of an actuator (17, 20 to
 35. The methodin accordance with claim 34, characterized in that a value of anamplitude and/or a frequency of vibrations are changed by means of theactuator (17, 20 to 31).